Calling the billing a mistake, Rubio said in a written statement that he will repay the party about $3,000 to cover the flights because the trips in 2007 were for state business, not politics.

On Wednesday, in response to questions from the St. Petersburg Times and Miami Herald about his party credit card, Rubio said the GOP paid for all travel when he served as speaker in 2007 and 2008. But records released to the Times/Herald on Thursday afternoon show that eight flights from South Florida to Tallahassee were also billed to the state.

"Billing the party was a mistake which needs to be fixed," Rubio said in the statement. "So, out of an abundance of caution, I am personally reimbursing the party for the cost of all eight flights."

He said his travel was arranged by a travel agency and his staff, and that the agency on several occasions applied charges to his party credit card instead of his personal one. Then staffers unknowingly sought reimbursement for the same flights from the state, Rubio said, though he personally signed off on each voucher.

The credit card blunder represents Rubio's first major setback since his campaign rocketed ahead of the one-time heavy favorite for Florida's open Senate seat, Gov. Charlie Crist.

"Certainly this has eroded some of the support Rubio had," said Republican consultant Chris Ingram, a Rubio supporter from Tampa. "When you project yourself as something of a Boy Scout and people start seeing you're not much different than a lot of these other guys, that can be damaging."

Rubio's campaign tried to put a positive spin on his double-billing: By charging the party for almost all of his travel, he saved taxpayers $32,000. It has also accused the Crist campaign and its supporters of leaking internal party records.

"If he wants to find out who to blame for this, he should look in the mirror," Crist said Friday at a road construction project in Davie. "He is the one who made these charges, not me, not any of my friends."

The governor did not have a party credit card, but he acknowledged Friday that some of his own expenses for party business were picked up by the former state chairman, Jim Greer, who was ousted from the party this month amid allegations of financial mismanagement.

"They never paid for anything personal for me," Crist said.

Rubio says he covered all personal expenses on his party credit card in payments to American Express in 2007 and 2008 totaling $16,052. Those personal expenses include $181.56 at the Museum of Natural History in New York, a $10.50 movie ticket and more than $10,000 for 20 rooms at a Georgia resort where his extended family celebrated his swearing-in, according to records obtained by the Times/Herald.

His campaign said Friday that it had not identified any additional expenses that need to be repaid. The credit card records, however, indicate that at least some of Rubio's personal expenses were covered by the party.

Rubio has identified at least $1,265 in personal expenses billed to the card between March and November 2008: $1,024 in charges from a Tallahassee property management company, and $241 for a flight to Las Vegas after the death of a relative.

But during that eight-month period, Rubio repaid only $982 toward the credit card, the records show. Rubio's campaign would not provide a list of all the personal expenses he repaid.

"We are accountable to Speaker Thrasher (state Sen. John Thrasher, the new state party chief), the Republican Party of Florida, its donors and activists, not the media or the Crist campaign," campaign adviser Todd Harris said in a statement. "The RPOF is conducting a full internal audit and we will fully participate if asked."

The party paid the rest of Rubio's $109,000 in credit card bills over two years, which included a $412 charge at All Fusion Electronics in Miami on April 24, 2007, a day when travel records show he was in Tallahassee. The campaign says the bill was for "computer repairs."

Willie Meggs, the state attorney in Tallahassee whose criminal inquiry of former lawmaker Ray Sansom first revealed the extent of the credit card use within the state GOP, said Friday that he is not investigating Rubio's spending.

"If the trip was a legitimate state trip, and the state paid for it, then I would say that's okay. Then the state of Florida is not a victim," Meggs said. "If he got reimbursed some other way, then he is sort of double-dipping. I think that could be an issue."

Rubio was among at least half a dozen high-ranking Republican lawmakers and an undetermined number of senior party staffers given party credit cards in recent years. Now they face the awkward question of whether the party should release all of the credit card statements to clear the air and reassure donors.

But incoming Senate President Mike Haridopolos and incoming House Speaker Dean Cannon released a joint statement Friday saying the professional auditors should be "allowed to do their job without the interference of a media circus surrounding the release of any records."

Miami Herald staff writers Alfonso Chardy and Michael Vasquez contributed to this report. Beth Reinhard can be reached at breinhard@herald.com.